chemical reactions
What type of reaction happens when two substances combine to make one new substance?
Synthesis
Name one clue that a chemical reaction has happened.
Color change / gas produced / temperature change / precipitate forms / light produced
What is the smallest unit of matter that keeps the properties of an element?
Atom
What is the difference between an open system vs closed system?
open system- no lid
closed system- lid
What law states matter cannot be created or destroyed?
Law of conservation of mass
What type of reaction breaks one compound into simpler substances?
Decomposition
Bubbling during a reaction usually means what is being produced?
Gas
molecule
What happened to the mass of the steel wool after it burned?
The mass increased
If my reactants are 100 grams how many grams should my products be?
100 grams
What type of chemical reaction takes placewhen one element replaces another
Replacement or Recombination
If a reaction releases heat, it is called what kind of reaction?
Exothermic
What are the reactants in a chemical equation?
The starting substance
What gas from the air bonded with the steel wool during the reaction?
Oxygen
Rusting iron is an example of what kind of change?
chemical change
Why must chemical equations be balanced?
Law of conservation of mass
If a reaction absorbs heat from its surroundings, it is called what?
Endothermic
What are the products in a chemical reaction?
The ending substance
Burning steel wool is an example of what kind of change?
chemical change
Difference between a physical and chemical change?
Physical change does not create something new while a chemical change does
Give an example of a chemical property
Flammability, oxidation (rust), Toxicity
Is a change in mass enough evidence to say that a chemical reaction took place?
No, change in mass could be a physical change as well
What happens to the atoms during a chemical reaction
They rearrange to form new substances
Why did the mass increase after the steel wool burned?
Oxygen atoms from the air bonded to the iron, adding more matter.
What is needed to keep a candle lit?
Oxygen so if it covered, the fire will go out